1. Field of the Invention
The present invention relates generally to the field of molecular and cellular biology. More particularly, it concerns methods for producing midbrain dopaminergic neuronal cells from stem cells, such as induced pluripotent stem (iPS) cells.
2. Description of Related Art
Cell populations that retain the ability to differentiate into numerous specialized cell types are useful for developing large numbers of lineage specific differentiated cell populations. These lineage specific differentiated cell populations are contemplated to find use in cell replacement therapies for patients with diseases resulting in loss of function of a defined cell population. In addition to their direct therapeutic value, lineage specific differentiated cells are also valuable research tools for a variety of purposes including in vitro screening assays to identify, confirm, and test for specification of function or for testing delivery of therapeutic molecules to treat cell lineage specific disease.
In the case of Parkinson's disease, for example, it is the loss of midbrain dopaminergic (DA) neurons that results in the appearance of disease symptoms. Thus, there is need for methods of producing DA neuronal cells from pluripotent cells, since such cells could be used both therapeutically and in disease models, e.g., to identify new therapeutics for treatments for Parkinson's disease. However, conventional methods for differentiating DA neurons (see, e.g., Perrier et al., 2004) resulted in cell populations that exhibited poor in vivo engraftment and displayed markers that were inconsistent with authentic midbrain DA neurons. Recently, Studer and colleagues were able to address these deficiencies and developed a protocol that allowed for differentiation of authentic midbrain DA neuronal cells, which are able to efficiently engraft in vivo (see, PCT Publn. No. WO2013/067362 to Studer et al., incorporated herein by reference). The methods and compositions provided herein expound upon the methods of Studer et al. to provide enhanced differentiation efficiency and high purity midbrain DA cell populations.